Interrupter for electrical ignition apparatus for internal-combustion engines having a device for adjusting the time of sparking.



G. UNTERBERG.

APPLIOATION FILED OUT. 10, I911.

Patented Feb. 17, 191i Fig.2

INTERRUPTEB FOB ELECTRICAL IGNITION APPARATUS FOR INTERNAL COMBUSTION ENGINES HAVING A DEVICE FOR ADJUSTING THE TIME OF SPANKING.

W277i ewes UNITED STATES PATENT OFFICE.

GUSTAV UNTERBERG, F DURLACH, GERMANY.

INTERRI TPTER FOR ELECTRICAL IGNITION APPARATUS FOR INTE BNAL-GOMBUSTION ENGINES HAVING A DEVICE FOR ADJUSTING THE TIME OF SPABIHNG.

Specification of Letters Patent.

Patented Feb. 17,1914.

Applioat'ionfiled October 10, i911. Serial No. 658,942.

To all whom it may concern:

Be it known that I, GUSTAV Un'rnnnnnc,

' in the firm of Unterberg and Helme at Durlach, Germany, a citizen of the German Empire, residing at Durlach, Baden, Germany, have invented certain new and useful improvements in interrupters for electrical ignition apparatus for internal-combustion engines having a device for adjusting the time of sparking, of which the following is a specification.

This invention relates to a novel construction'of electrical sparking apparatus for internal combustion engines in which the time of sparking is automatically adjusted according to the speed of the engine.

It has already been proposed to adjust the rotating cam of an interrupter provided with wedge shaped lateral parts against the action of a spring by means of a special regulator. As is well known, the period of ignition should vary according to the speed of the engine in order to attain the greatest efliciency. Thus, at a high speed, the ignition should take place at an earlier position of the piston than when the engine is run ning at a low speed. This regulation of the ignition period according to the speed of the engine is also for the purpose of preventing injurious hammering and objectionable noise. The automatic ignition period shifters heretofore generally used consist of devices for changing the position of one of the parts which determine the production of the igniting spark.

According to the present invention the pivoted interrupting lever carries the ignition period regulator which consists of a cam movable radially 'on said lever by centrifugal force opposed to rasilient means tending to hold said cam at the inner extremity of its movement, said regulator being designed to cooperate with a fixed cam which is shaped to engage the cam on the lever earlier as said movable cam is thrown farther out by increassubject to the constant up and down movement of the interrupting lever, so' that said cam is in an almost constant state of agita tion which serves to prevent the cam from becoming clamped or stuck in its guiding slot in the lever.

The invention will now be more particuthe letter 0 denotes the stationary interrupter casing in which there is mounted in suitable bearingsa lever d. This lever is secured upon springs e and-carries the electrical contact piece I) and the cam 0.

The cam c itself is movably' mounted on the end of the lever 03 as may be clearly seen in Figs. 2 and 3 and is under the control of a spring 7. As illustrated, the cam c is mounted to slide in a radial slot 0 the spring being attached to the outer end 0 which projects through said slot. According to the speed of revolution, the cam 0 will be moved out more or less by centrifugal force against the action of the spring 6. g. to one of the positions indicated in dotted lines at I, II, III in Fig. 2. The result of this is that the displacement of the lever d, which causes the interruption between the movable contact I) and the fixed contact I), Fig. 1, is caused to take place at an earlier or later time within limits corresponding to the angle. Obviously the stationary cam g in the interrupter casing must be suitably shaped for the purpose, so that the farther the cam 0 is moved from the center of rotation, the sooner it will be engaged by the cam g, as clearly shown in Fig. 2. This fixed cam g is made in the shape of an inclined vaulted body, as illustrated in Fig. 3. The cam on the lever-is obliged to ride over said fixed cam, thus breaking the circuit between the contacts I) and 12 The arrangement illustrated is only one possible construction. Obviously the regulation may be effected in many different ways.

Having thus described my invention what I claim as new and desire to secure by Letters Patent 0f the United States is:

1. In an interrupter for electrical ignition apparatus for internal combustion engines, the combination with an electrical contact, of a lever, a second electrical contact on said lever, resilient means for normally holding said lever in with its contact enga 'ng the first mentioned contact, a cam on t e inner surface of the leveradapted to move radially thereon under centrifugal force, resilient means acting in opposition to said centrifugal force, and a fixed cam arranged in the path of rotation of the movable cam and shaped to be engaged by the latter earlier in its rotation as it is thrown farther from the center of rotation by increasing centrifugal force due to accelerated speed of the engine.

2. In an interrupter for electrical ignition apparatus for internal combustion engines, the combination with an electrical contact, of alever provided with a radial slot, a second electrical contact on said lever, resilient means for normally holding said lever in with its contact engaging the first mentioned contact; a cam arranged to slide in the slot in the lever under centrifugal force and projecting from the inner surface "of said lever, resilient means acting in opposition to said centrifugal force, "and a fixed cam arranged in the ath of rotation of the movable cam and shaped to be engaged by the latter earlier in its rotation as it is thrown farther from the center of rotation by increasing centrifugal force due to accelerated speed of the engine.

3. In an interrupter for electrical ignition apparatus for internal combustion engines, the combination with, an electrical contact, of a lever, a second electrical contact carried by said lever, means for holding said lever with its contact engaging the first mentioned contact, a cam on the inner surface of said lever adapted to move radially thereon under centrifugal force, means acting in opposition to said centrifugal force, and a fixed cam arranged in the path of rotation of the movable cam and adapted to be engaged thereby during certain periods of its rotation.

In testimony whereof I afiix my signature, in presence of two witnesses.

GUSTAV UN TERBERG.

Witnesses:

FRIEDRICH CARL WVENTZEL, MAX DEUTSCHER. 

